English tenses are organized into THREE primary times (present/past/future) EACH with FOUR aspects (simple, continuous/progressive, perfect, perfect continuous) — giving 12 total tense forms — e.g., 'I eat' (present simple) vs. 'I have been eating' (present perfect continuous), each conveying a DIFFERENT precise time-relationship.

• ›Recognizing tense as conveying NOT just WHEN an action happens but its COMPLETION status and DURATION (via the aspect dimension) is the chapter's foundational conceptual point
• ›CORRECT tense usage is among the MOST frequently tested grammar skills in competitive exams